AS AIDS IN THE DETERMINATION OF SPECIES. . 37 



Wood-curve (see Fig. 30). — Body thickened and elevated, horns generaUy not 



much incurved. 

 Vessels. — Largest, ^ in. 



Average, about half that. 



Moderately large, numerous, and generaUy distributed. 

 Characteristic features : 

 Section. — Small. 



Cortical Cavities. — Moderately large and numerous. 

 Hard Bast.- — Feebly developed. 



Wood-curve. — With thickened body, and generally elevated horns. 

 Vessels. — Moderately large, numerous, and generally distributed. 



21. E. maailaf a, Hooker ; spotted gum. 



Tree. — Tall, handsome. 



Leaves. —Often very large and coarse, and equally green on both sides. 



Size of Section. — 1 line broad by f line thick, or about IJ times broader than 



thick. 

 Outline of section. — Oval, flattened on upper surface. 

 Epidermis. — Thickness, about ^^ in. 



Breadth, about half that. 

 Cortical Cavities. — ^ in. oval to round, numbering from 6 to 2. 

 Central Canals. — Normally 2, oval to roimd ; largest, about ^ in., or generally 



the size of the cortical cavities. 

 Crystals. — Numerous. 



Hard Bast. — In closely adjoining patches, generally a few cells thick. 

 Wood-curve (see Fig. 31). — Usually of equal thickness throughout, with very 



gently incurved horns, each about one-third of body-length. 

 Vessels. — Largest, about ~ in. 

 Average, 4 — i in. 



Moderately large and numerous, confined almost exclusively to upper 

 and middle portion of wood. 

 Characteristic features : 



Section. — Of average size. 



Cortical Cavities. — Medium-sized, not very numerous. 



Central Canals. — Normally 2, about same size as cortical canals. 



Hard Bast. — Li contiguous patches, a few cells thick. 



Wood-curve. — Of equal thickness throughout, with very gently incurved 



horns. 

 Vessels. — Moderate in size and number, and absent from lower portion of 

 wood. 



